feat(EMBEDDINGS-0001): enable local embedder by default and overhaul settings page

- Wire local embedding provider as the default on startup when no profile is configured
- Refactor embedding settings into dedicated service, DTOs, mappers and models
- Rebuild settings page with profile management UI and live test feedback
- Expose index summary (indexed versions + embedding count) on repo endpoints
- Harden indexing pipeline and context search with additional test coverage

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/server/models/embedding-profile.ts

@@ -0,0 +1,77 @@
+export interface EmbeddingProfileEntityProps {
+	id: string;
+	provider_kind: string;
+	title: string;
+	enabled: boolean | number;
+	is_default: boolean | number;
+	model: string;
+	dimensions: number;
+	config: Record<string, unknown> | string | null;
+	created_at: number;
+	updated_at: number;
+}
+
+export class EmbeddingProfileEntity {
+	id: string;
+	provider_kind: string;
+	title: string;
+	enabled: boolean | number;
+	is_default: boolean | number;
+	model: string;
+	dimensions: number;
+	config: Record<string, unknown> | string | null;
+	created_at: number;
+	updated_at: number;
+
+	constructor(props: EmbeddingProfileEntityProps) {
+		this.id = props.id;
+		this.provider_kind = props.provider_kind;
+		this.title = props.title;
+		this.enabled = props.enabled;
+		this.is_default = props.is_default;
+		this.model = props.model;
+		this.dimensions = props.dimensions;
+		this.config = props.config;
+		this.created_at = props.created_at;
+		this.updated_at = props.updated_at;
+	}
+}
+
+export interface EmbeddingProfileProps {
+	id: string;
+	providerKind: string;
+	title: string;
+	enabled: boolean;
+	isDefault: boolean;
+	model: string;
+	dimensions: number;
+	config: Record<string, unknown>;
+	createdAt: number;
+	updatedAt: number;
+}
+
+export class EmbeddingProfile {
+	id: string;
+	providerKind: string;
+	title: string;
+	enabled: boolean;
+	isDefault: boolean;
+	model: string;
+	dimensions: number;
+	config: Record<string, unknown>;
+	createdAt: number;
+	updatedAt: number;
+
+	constructor(props: EmbeddingProfileProps) {
+		this.id = props.id;
+		this.providerKind = props.providerKind;
+		this.title = props.title;
+		this.enabled = props.enabled;
+		this.isDefault = props.isDefault;
+		this.model = props.model;
+		this.dimensions = props.dimensions;
+		this.config = props.config;
+		this.createdAt = props.createdAt;
+		this.updatedAt = props.updatedAt;
+	}
+}

src/lib/server/models/embedding-settings.ts

@@ -0,0 +1,20 @@
+import type { EmbeddingProfile } from './embedding-profile.js';
+
+export interface EmbeddingSettingsProps {
+	profiles: EmbeddingProfile[];
+	activeProfile: EmbeddingProfile | null;
+}
+
+export class EmbeddingSettings {
+	profiles: EmbeddingProfile[];
+	activeProfile: EmbeddingProfile | null;
+
+	constructor(props: EmbeddingSettingsProps) {
+		this.profiles = props.profiles;
+		this.activeProfile = props.activeProfile;
+	}
+
+	get activeProfileId(): string | null {
+		return this.activeProfile?.id ?? null;
+	}
+}